This project is designed to investigate the effects of environmental pollutants like chlordecone (Kepone) and mirex on the neuronal and cardiac uptake of dopamine and norepinephrine in rats. The effects of these chemicals on neuronal and myocardial ATPases will also be determined in order to assess the role of ATPase (Na-pump) in the uptake process of the catecholamines. It has been postulated that the uptake processes of the catecholamines by central nervous system and other tissues is energy dependent and coupled to active membrane transport, possibly to Na ion-K ion ATPase. The inhibitors of Na ion-K ion ATPase, like ouabain, inhibited the uptake of dopamine and norepinephrine. Our results show that chlordecone is a potent inhibitor of ATPases in several tissues and it is quite possible that it may interfere with the uptake processes of the catecholamines. Mirex, a close structural analog of chlordecone, did not inhibit the ATPase system. By using two closely related compounds having dissimilar effects on the ATPase system one could determine the role of ATPase in the the uptake processes of the catecholamines. The data obtained from the proposed project would also help us in assessing the toxicity of chlordecone and mirex to mammalian central nervous system and heart.